The interdisciplinary "Colloquium Reichsstadt Frankfurt" (corf) exists since summer 1999. Here, scientists have joined together who under various aspects wish to research the history of Frankfurt am Main in the Middle Ages and earlier modern times. The foundation idea stemmed from interlinking a practical network: i.e. both the mutual help in accessing archives and research literature as well as the discursive interchange of research findings are essential aspects of the work of the group. The personal and institutional independence of the group has shown to be conducive to free discussion and subject-oriented work.